get stronger. that's it. dont sacrifice performance just to get "big". Size is not always a function of strength, I know a lot of skinnier players who are strong as hell. By the same token, I know a lot of big dudes who are fast as hell.

You can workout but if your performance suffers you are probably not doing workouts that are customized to your playing ability or goals as a player. forget the whole getting big will make you slower and all that, that's the wrong thought process in the first place. Do the right workouts and you will get stronger without sacrificing performance.